Abstract 15432: Observation of Aortic Dilatation in Congenital Conotruncal Anomalies - Tetralogy of Fallot, Double Outlet Right Ventricle and Truncus Arteriosus

Backgrounds: Dilatation of aortic root or ascending aorta is often seen in the patients with conotruncal anomalies (CA). How fast these structures dilate and how we manage this phenomenon are not clear. Methods: We reviewed medical records of patients who underwent biventricular repair of CA such as tetralogy of Fallot (TOF), double outlet right ventricle (DORV) and truncus arteriosus (TA) from 2004 to 2018. We included 99 patients who had follow-up cardiac computed tomography angiography (CT) images at least 5 years since initial CT in this study. We analyzed changes of diameters of aortic root structures and ascending aorta between initial and follow-up CT images. Results: Median follow-up duration was 16.1 years (interquartile range (IQR): 11.8~26.2 years) after operation. Median interval between initial and follow-up CT examination was 9.4 years (IQR: 7.1~11.5 years). Median age of initial and follow-up CT was 4.3 years (IQR: 0.3~12.3 years) and 14.4 years (IQR: 9.2~22.9 years). The median z-scores (with IQR) of sinus of Valsalva (SV, 2.0 (0.8~3.3) → 2.4 (1.4~3.3), p=0.006) and sinotubular junction (STJ, 1.3 (-0.2~2.6) → 2.2 (0.4~3.3), p=0.001) were significantly changed, whereas aortic annulus (AA, 2.4 (0.9~3.4) → 2.3 (0.8~3.3), p=0.21) and ascending aorta (AsA, 1.6 (0.4~2.9) → 1.6 (0.03~2.6), p=0.27) did not show significant changes in CT images. Median increasing rate of diameter of AA, SV, STJ and AsA was 0.72, 0.93, 0.83 and 0.51 mm/year, respectively. Dilatation rate of AA (0.69 in TOF vs. 0.99 in TA, p=0.042) and SV (0.81 in TOF vs. 1.53 in TA, p=0.008) of TA was significantly higher than of TOF. Conclusions: In TOF, DORV and TA, SV and STJ significantly dilated, whereas AsA and AA did not significantly dilated for 9 years of follow-up. Although chance of surgical intervention for dilatation of aortic structures was rare, it might be necessary to observe closely aortic valvular function associated with structural deterioration of SV or STJ.